TREATMENT OF WASTEWATER WITH HIGH FAT CONTENT EMPLOYING AN ENZYME POOL AND BIOSURFACTANT: TECHNICAL AND ECONOMIC FEASIBILITY

ABSTRACT The combination of 0.5% weight per volume (w/v) crude enzyme consortia produced by solid state fermentation with Penicillium brevicompactum and 27 milligrams per liter (mg/L) of rhamnolipid biosurfactant produced by submerged fermentation with Pseudomonas aeruginosa was employed to pretreat wastewater from a poultry slaughterhouse in bench upflow anaerobic sludge blanket (UASB) bioreactors. One bioreactor was fed with untreated wastewater (Control) and another with pretreated wastewater (Test). Under an organic loading rate of 11 kg COD/m3.d, the Test bioreactor showed higher specific methane production (67.8 mL CH4 (STP)/g COD removed), higher chemical oxygen demand (COD) (91.2%), and oil and grease (O&G) (95.8%) removal than the Control bioreactor, which produced 36.1 - 16.9 mL CH4 (STP)/g COD removed with 72.5% COD removal and 48% O&G removal. The Control bioreactor experienced five clogging episodes due to the accumulation of fat on the surface, while the Test bioreactor operated without operational problems. The scum of the Control bioreactor contained more than 10 times higher quantities of fat than the Test bioreactor. The economic analysis indicated that such alternative technology has lower costs than conventional technology.

摘要：将短密青霉（Penicillium brevicompactum）固态发酵制备的0.5%质量体积比(w/v)粗酶复合体系，与铜绿假单胞菌（Pseudomonas aeruginosa）深层发酵制备的27毫克每升(mg/L)鼠李糖脂生物表面活性剂复配，用于家禽屠宰场废水的预处理，并开展台式上流式厌氧污泥床（UASB）生物反应器实验。设置两组反应器：一组以未经预处理的屠宰废水为进水（对照组，Control），另一组以经上述预处理的废水为进水（实验组，Test）。在有机负荷率为11 kg COD/m³·d的运行条件下，实验组反应器的比甲烷产率（67.8 mL CH₄(标准温压条件, STP)/g 去除COD）、化学需氧量(COD)去除率（91.2%）以及油脂(O&G)去除率（95.8%）均优于对照组；对照组的比甲烷产率为36.1~16.9 mL CH₄(标准温压条件, STP)/g 去除COD，COD去除率72.5%，油脂去除率仅为48%。对照组反应器因脂肪在器壁表面积累先后发生5次堵塞事件，而实验组反应器运行全程未出现任何故障。对照组反应器浮渣中的脂肪含量为实验组的10倍以上。经济分析结果表明，该替代预处理工艺的成本低于传统处理工艺。